In this recipe, we create a DAO method to retrieve a database row, which we will use to create an object.
Use an SQL select query and create an object from the result using RowMapper:
In the DAO class, add an inline class implementing
RowMapper. This class defines how to generate aUserobject from a database row:private class UserMapper implements RowMapper<User> { public User mapRow(ResultSet row, int rowNum) throws SQLException { User user = new User(); user.setId(row.getLong("id")); user.setFirstName(row.getString("first_name")); user.setAge(row.getInt("age")); return user; } }Add a DAO method which will perform an SQL
selectquery and use aUserMapperobject to generate aUserobject:public User findById(Long id) { String sql = "select * from user where id=?"; User user = jdbcTemplate.queryForObject(sql, new Object[]{id}, new UserMapper()); return user; }